Raised floor panel and assembly

ABSTRACT

Disclosed is a raised floor panel and panel assembly for computer and similar installations. The panels are supported above a subfloor on pedestals and are easily installed and removed for later access to the space beneath the floor. Each panel comprises a core with or without strengthening metal sheets about which is wrapped a flexible and at least partially resilient floor covering, such as carpet or flexible tile material. The floor covering extends over the edges and for a short distance beneath each panel.

United States Patent Bettinger [451 Aug. 8, 1972 [541 RAISED FLOOR PANELAND 3,067,843 12/1962 Rushtoh et a] ..52/ l 26 ASSEMBLY 3,065,50611/1962 Tremer ..$2/126 [72] Inventor: hm mm, Elkridge, 2,605,514 8/1952Eshenaur et al. ..52/273 [73] Assignee: United Fabricating Company,Inc., P i Examiner-Hampton Hunter Elkl'ldge, Attorney-Le Blanc 8!. Shut22 Filed: March 30, 1970 l 1 [57] ABSTRACT [21] App1.No.: 23,531

Disclosed is a raised floor panel and panel assembly for computer andsimilar installations. The panels are [52] 11.8. C1. ..52/l26, 52/273,52/600 supported above a bfl on pedestals and are easily [51] Int. S/43installed and removed for later access to the space [58] Fieldoi Search..52/126, 273, 177, 390, 599, beneath the floor. Each panel comprises acore i h 52,600 267 or without strengthening metal sheets about which iswrapped a flexible and at least partially resilient floor [56]References cited covering, such as carpet or flexible tile material. Then- STATES p m floor covering extends over the edges and for a shortdistance beneath each panel. 3,012,919 12/1969 Janney ..52/273 3,318,0575/1967 Norsworthy ..52/ 126 6 Claims, 10 Drawing Figures PAIENTEDA E 93.681.882

SHEET 10F 3 INVENTOR JAMES H BETTJNGER 50 05 BY $6268 4 QM AT TURNERRAISED FLOOR PANEL AND ASSEMBLY This invention relates to raised floorpanels and to raised floor panel assemblies, and more particularly toapparatus of this type of simplified and inexpensive construction whichreduces the cost of manufacturing and assembling raised or elevatedfloors.

Modern computer installations employing advanced computer equipmentrequire a carefully planned and completely coordinated environment.Today's sophisticated equipment must be provided with temperature andhumidity control, air filtration, traffic and noise restrictions, and awide variety of other flexible facilities for the machines and theiroperators. Provision must be made for future expansion, in the form ofnew or modified equipment.

For these and other reasons, many modern computer installations areprovided with what are commonly referred to as raised or elevatedfloors. These floors generally take the form of removable rectangularfloor panels or tiles supported in spaced relation above a suitablesubfloor by a metal lattice of criss-crossing grids and supportingcolumns. Conduits, such as electrical cabling, air conditioningequipment, and the like, pass between the subfloor and the floor to thecomputer circuits and associated equipment. In some instances, the spacebetween the tow floors may be used as a plenum to supply conditioningair to various parts of the room. In all cases the removability of thepanels provides great flexibility in making it possible to addadditional cabling or to service the computer equipment as the needarises.

The present invention is directed to an improved panel and panelassembly for raised floors of this general type and is particularlydirected to a construction which substantially lessens the cost ofmanufacturing and installing the floor. In the present invention, thecustomary floor tile covering for the panels and the accompanyinglateral trim edge is replaced by a flexible and preferably at leastslightly resilient floor covering material which not only extends overthe top surface of the floor panels, but also along the edges andpreferably for a short distance along the underside of each panel. Inthe preferred embodiment, the floor covering takes the form of a carpetwith sufficient resiliency that the abutting edges of adjacent panelsform an air seal to define a plenum beneath the raised floor. Animportant feature resulting from the use of a flexible floor coveringmaterial extending over the top and side edges of the panels is that thepanel cores need not be held to close tolerances and materials such aslight weight concrete may be used as the cone. At the same time, theresiliency of the carpet material permits slight adjustment forvariations in panel size from panel to panel and further provides foreasy installation and removal of the panels due to the resiliency withwhich they abut. Additional advantages include the fact that theflexible and resilient nature of the carpeting material achieves a sounddampening and cushioning feature for the floor system by eliminating anymetal-to-metal contact and the utilization of a continuous covermaterial eliminates static electricity buildup in the walking surface ofeach panel by allowing the static electricity buildup to follow anatural path to ground. Since the wraparound floor covering material isin contact with the metal understructure which is conventionallyconnected at spaced points to a central grounding system, all staticelectricity is conducted to ground.

It is therefore one object of the present invention to provide animproved panel for raised floors.

Another object of the present invention is to provide an improved raisedfloor system of simplified and less expensive construction.

Another object of the present invention is to provide an improved paneland raised floor system which substantially reduces the cost ofmanufacturing and installing the floor.

Another object of the present invention is to provide an improved paneland floor panel assembly permitting the use of a wide variety of panelcores which need not be manufactured to close tolerances.

Another object of the present invention is to provide a raised floorpanel and panel assembly in which the top surface and side edges of thepanels are each covered by an integral layer of floor carpeting.

Another object of the present invention is to provide a raised floorpanel in which a conventional pile carpet extends over the top, alongeach side edge, and for a short distance along the bottom and round theentire periphery of each panel.

Another object of the present invention is to provide an elevated orraised floor panel system in which each panel comprises a concrete corecovered on at least all but one side by a flexible and resilient floorcovering material, such as carpeting or the like.

These and further objects and advantages of the invention will be moreapparent upon reference to the following specification, claims, andappended drawings, wherein:

FIG. 1 is a perspective view of a portion of a raised floor assemblyconstructed in accordance with the present invention;

FIG. 2 is a partial cross section through the raised floor assembly orsystem of FIG. 1;

FIG. 3 is an enlarged view of a support pedestal, grid, and abuttingpanel junction in the system of FIGS. 1 and 2;

FIG. 4A is a perspective view showing the top and two side edges of afloor panel;

FIG. 4B is a similar perspective view showing the bottom and other twoside edges of the panel of FIG. 4A;

FIG. 5 is a perspective view of a modified floor panel with parts cutaway to show the carpet attached directly to the core;

FIG. 6 is a partial elevational view corresponding to that of FIG. 3showing a portion of a raised floor assembly in which the metal gridworkis omitted;

FIG. 7 is a partial cross section through a modified floor panelconstructed in accordance with the present invention;

FIG. 8 is a partial cross section through a further modified floor panelconstructed in accordance with this invention; and

FIG. 9 is a view similar to FIGS 3 and 6 showing a still furthermodified elevated floor assembly.

Referring to the drawings, a portion of a raised floor systemconstructed in accordance with the present invention is generallyindicated at 10 in FIG. 1. The system is illustrated as underconstruction in a room including walls I2 and I4 and a subfloor l6.Adhesively secured or otherwise suitably attached to the subfloor are aplurality of pedestals 18 in the form of adjustable metal columnsupports for a plurality of identical rectangular floor panels 20. Someof the panels 20 in FIG. I are omitted to show the underlying supportpedestals I8 and the overall metal grid generally indicated at 22. Thegrid 22 comprises longitudinal and transverse grid members or stringers24 and 26 supported by and preferably attached to the heads or caps ofeach of the pedestals 18. Various pedestal and grid constructions arepresently available and any of the well known structures may be used inthe present invention. In the preferred embodiment, pedestals I8 areplaced on 24 inch centers and the panels 20 are preferably square andapproximately 2 feet on each side.

Referring in particular to FIGS. 2 and 3, pedestals 18 each comprise abase 28 welded, brazed, or otherwise suitably secured as indicated at 30in FIG. 3 to one end of a threaded metal stud 32. The upper end of stud32 is received in the hollow lower end of metal tube 34. The upper endof this tube is again welded, brazed, or otherwise suitably attached asat 36 to the underside of a pedestal cap or head 38. The telescopingrelationship between stud 32 and tube 34 may be adjusted by a pair ofmetal leveling nuts 40 and 42 to vary and adjust the height of thepedestal 18. Base 28 of the pedestal is preferably attached to subfloor16 with adhesive but may be secured in any desired manner. Likewise, cap38 of the pedestal may be attached to the stringers 24 and 26 in anyconventional manner. In some systems, the pedestal head includesprojections over which the stringers are slidably received to secure andlock the stringers to the pedestal. In other constructions, thestringers are attached by bolts and nuts to the head of the pedestal. Inthe embodiment shown, the stringers 24 and 26 are preferably all ofequal length, i.e., nominally 2 feet, and are slid over suitableprojections on the head of pedestal. It is understood that the presentinvention is equally applicable to other grid assemblies in which thestringers are bolted to the pedestals and in which individual integralstringer elements may span more than two adjacent pedestals, i.e., maybe 4 feet or more in length.

Resting on the stringers 24 and 26 nd forming made important part of thepresent invention are the novel floor panels 20. Each panel is identicalin construction and preferably each is 24 inches on a side to have asquare configuration on the order of l to 2 inches thick. As best seenin FIG. 3, each of the panels comprises a core 50 approximately 1 inchthick and made of suitable material, such as a high density particleboard, i.e., compressed wood particles. Overlying the upper and lowersurfaces of core 50 are flat rectangular sheets 52 and 54 preferablymade of galvanized steel. Steel sheets 42 and 54 are preferably securedto the opposite surfaces of panel 50 by a suitable adhesive layer (notshown). Finally, the top or walking surface of the panels 20 is formedby a layer 56 of flexible and preferably somewhat resilient material,which by way of example only may take the form of a conventional allwool looped pile floor carpeting. The carpet extends integrally with thelayer 56 over the edge of the panel as indicated at 58 and for a shortdistance along the panel bottom as indicated at 60. It is understoodthat the carpet 56 extends integrally over all four edges of the paneland includes a bottom portion 60 along each of these four edges, in allinstance integral as illustrated in FIGS 4A and 4B. The carpet ispreferably secured to the metal plates and to the edges of the core bysuitable adhesive (not shown).

While the covering material is preferably conventional floor carpet, itis apparent that other flexible and at least slightly resilientmaterials may be used, such as certain tiles and at least partiallyresilient vinyl materials possessing sufficient flexibility to bewrapped around the side edges and the bottom of the panels. Adhesiveswhich may be used to bond the steel sheets to the cores and to bond thecarpet or other floor covering material to the remainder of the panelsinclude conventional two-part epoxy adhesive and conventionalrubber-base, two surface adhesives with contact bonding at bothsurfaces. In certain instances, where load requirements permit, thesteel sheet 52 and 54 may be omitted and the carpet 56 bonded directlyto the core 50.

An important feature of the present invention includes the fact that theresiliency of the covering material 56 wrapped around the edges and theunderside of the panels makes it possible to utilize a variety of corematerials which were unsuited to prior raised floor panels due to theclose panel tolerances which had to be maintained. That is, theresiliency of the covering material at the abutting edges of adjacentpanels 58 automatically compensates for variations in core sections 50from panel to panel such that a variety of core materials may be used,some of which while having exceptional strength are diflicult tomanufacture in quantity within the tolerances previously necessitated bythe metal edge and vinyl trim strip constructions of previous raisedfloor panels. For example, FIG. 6 shows a construction in which thefloor panels are of identical construction to the panels 20 previouslydescribed but with the exception that the cores 72 are made oflightweight and preferably expanded concrete. Because of the increasedstrength afforded by the concrete cores and where loading requirementspermit, the grid assembly 22 can be omitted and the pedestals 18, whichin this case are provided with a flat cap or head 74, directly supportabutting panels 70. The result is a substantial savings in the cost ofmanufacturing and assembling the raised or elevated floor.

FIG. 7 shows a modified panel in partial cross section in all respectsidentical to the panels 70 of FIG. 6 with the exception that theconcrete core 82 has embedded in it interconnected longitudinal andtransverse strands 84 and 86 of metal reinforcing rods to provide addedstrength to the core and overall panel. FIG. 8 shows a still furthermodification and illustrates in partial cross section a panel 90identical to the panels previously described but in which the core 92 isformed of several interconnected wood plies to form a plywood core ofincreased strength.

FIG. 9 shows a further modified panel and panel assembly with like partsagain bearing like reference numerals. In the embodiment of FIG. 9, thepanels 20' are in all respects identical to the panels 20 previouslydescribed with the exception that each of the edges has a verynoticeable taper, as indicated at 94, from the top to the bottom surfaceof the panel. The panels previously describe are all preferably madewith a slight taper from top to bottom to reduce the frictionencountered when the panels are inserted and particularly when they areremoved from adjacent panels. This taper has not been described inconnection with the previous embodiments since it is fairly slight andin any event is obscured by the resilient nature of the floor coveringmaterial when the edges of two panels are in abutment. The slight taperis indicated generally at 88 in FIGS. 7 and 8. In the embodiment of FIG.9, the taper 94 is much more pronounced to provide clearance for a rib96 formed along the top edge of the stringers, such as the stringer 26'illustrated. In this embodiment, the pedestal 18' is also modified toinclude an outwardly flaring head 98 suitably apertured to pass fourscrews (only one of which is indicated at 100) for securing a bracket ornut 102 to the end of the stringer 26'. To attach the stringer to thehead, the stringer is slipped into position with its lower flangesresting on head 98 but beneath nut 102. Screw 100 is then tightened toclamp the stringer by the nut to the top of the pedestal head. It isunderstood that the other three stringers fonning a corner junction forthe assembly of FIG. 9 are similarly secured to he pedestal 18'. Aground wire 104 is provided with a conductive eyelet 106 electricallyconnected to the metal stringer 26' by a second screw 108 and nut 110,screw 108 passing through a suitable aperture provided in the stringer.The other end of ground wire 104 is connected to the central buildingground system and one such wire [04 is preferably provided for each1,000 square feet of elevated floor area.

Important features of the present invention include the provision ofelevated floor panels in which a flexible and at least partiallyresilient floor covering material extends over the top of the panel andover the side edges and around the outer portion of the panel bottom.This makes possible the use of a variety of panel core materials sincethe resiliency and flexibility of the covering material, particularlyabout the abutting edges of adjacent floor panels, automaticallycompensates for variation in size of the core and makes possible the useof core materials which could not previously be economicallymanufactured to the required tolerances. in addition to the moreconventional fiberboard and pressed wood particle board panels, thepresent invention makes possible the use of other core material, such asgypsum board core, lightweight and preferably expanded concrete, eitherreinforced or not reinforced, and laminated wood paneling cores orplywood cores may also be used. In the preferred embodiment, the panelcovering material takes the form of a conventional pile carpet made ofwool, Nylon, or any of the other conventional carpet materials. Sincestronger core materials, such as the newer lightweight concrete, may beemployed, the floor panels of the present invention may be provided withincreased strength in certain instances permitting the elimination ofthe conventional metal gridwork so that the panels are directlysupported on pedestals as illustrated in FIG. 6. The panels arepreferably of square configuration approxi' mately 24 inches on a sideand may vary in thickness from approximately 1 to 2 inches or more,depending upon the panel size, panel material, and the loads to besupported. In certain instances, the covering material may be applieddirectly to the cores but where additional strength is required, thepanels may be provided with the upper and lower preferably galvanizedmetal sheets 52 and 54.

The resilient nature of the covering makes it possible to readily insertand remove a panel in spite of small variations in size from panel topanel since the cushioning outer cover material along the panel edgestends to give as the panel is inserted and removed. in addition, thecushioning action of the covering material extending along the fouredges at 60 on the under side of the panel provides a cushioning effectwhen the panel rests on the head 74 of FIG. 6 or on the stringers, suchas the stringer 26 of FIG. 3, so that there is no direct metal-tometalcontact between the stringer or head and the metal sheet 54. At the sametime, the resilient engagement of this lower edge 60 of the panel withthe support member and the similar engagement of the side edge 58 withan adjacent panel provides a multiple seal acting to seal the air spacebetween the panels forming the elevated floor and the subfloor 16 sothat this space, which may vary from a few to several inches in height,may be used as a plenum for supplying air to various locations in theroom. Finally, the integral nature of the wraparound floor materialprovides a natural path to ground through the floor carpet itself toeliminate static electricity buildup in the walking surface of eachpanel. By virtue of the wraparound floor covering in contact with themetal understructure, through lower edge 60 and the metal understructurebeing connected at appropriate points to a central grounding system asillustrated at 104 in FIG. 9, all static electricity tends to go toground. This is an important consideration for many computerinstallations since static discharge is considered harmful to the lowvoltage equipment employed in these installations. If desired, thecarpet material may be of the well known anti-static type so as tofurther reduce the likelihood of static buildup and discharge whichmight otherwise result from the motion of people, carts, furniture,etc., in contact with the floor covering material. Abrupt discharges ofthe static charges to metallic surfaces or other people can causediscomfort to personnel and may cause malfunction of the low voltageelectronic equipment.

This invention may be embodied in other specific fonns without departingfrom the spirit or essential characteristics thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

1. An elevated floor assembly comprising a subfloor, a plurality ofpedestals spaced about said subfloor, and a plurality of floor panelssupported by said pedestals in spaced relation above said subfloor, eachpanel comprising a rectangular core having top and bottom surfacesjoined by four edges, a flexible and at least partially resilient floorcarpet integrally overlying said tip surface and said edges of saidcore, portions of said carpet on adjacent panels overlying said edgesbeing in abutting contact with each other, said carpet also extendingintegrally along said bottom surface of each of said cores adjacent eachof said edges, said panel having a thickness on the order of l to 2inches with sufficient strength for use as a flooring in said elevatedfloor assembly, and static electricity discharge means engagsaid coresis of square cross section.

5. An assembly according to claim 1 wherein each of said cores is madeof non-metallic material, each panel including a metal sheet overlyingeach of said top and bottom core surfaces, said sheets extending betweensaid carpet and the respective surfaces of said cores.

6. An assembly according to claim 1 wherein each said core is made frommaterial selected from the group consisting of wood particle board,gypsum board, plywood, light-weight concrete, and light-weight concreteincluding metal reinforcing.

t i I 4' l UM'IEECD sinner: PNIEN'I OFFICE (TERIE EC AT 16 U IF CO H R E(If 1. ON

Inventor(s) JAMES H. BETTINGER It is cortifj c-d that error no -oars inthe aho 'eidvntifii ed atont i i and that said Letters Patent are herebycorrected as shown below:

In Col. 1, line 26, "tow" should read two--; line 51, "cone" should read-core--.

In Col. 3 line 43, "nd forming made" should read --and forming an--;line 55, "sheets 42" should read --sheets 52--; line 67, "instance"should read -instances--.

In Col. line 16, "sheet 52 should read --sheets 52-; line 65, "describe"should read --described--.

In Col. 5, line 21, "he" should read -the--.

In Col. 6, line 59, Claim 1, "tip" should read --top--.

In Col. 7 line 4, Claim 1, "mans" should read --means-- Signed andsealed this 30th day of January 1973.

(SEAL) Attest:

ROBERT GOTTSCHALK EDWARD M.FLETCHER,JR.

Commissioner of Patents Attesting Officer

1. An elevated floor assembly comprising a subfloor, a plurality ofpedestals spaced about said subfloor, and a plurality of floor panelssupported by said pedestals in spaced relation above said subfloor, eachpanel comprising a rectangular core having top and bottom surfacesjoined by four edges, a flexible and at least partially resilient floorcarpet integrally overlying said tip surface and said edges of saidcore, portions of said carpet on adjacent panels overlying said edgesbeing in abutting contact with each other, said carpet also extendingintegrally along said bottom surface of each of said cores adjacent eachof said edges, said panel having a thickness on the order of 1 to 2inches with sufficient strength for use as a flooring in said elevatedfloor assembly, and static electricity discharge means engaging theportions of said carpet extending along the bottom surface of the coreof at least some of said panels whereby static electricity in the carpetof said panels may be discharged through both said discharge mans andthe abutting carpet surface of adjacent panels.
 2. An assembly accordingto claim 1 including a grid of metal stringers spacing said panels fromsaid pedestals.
 3. An assembly according to claim 1 wherein saidpedestals directly support said panels above said subfloor.
 4. Anassembly according to claim 1 wherein each of said cores is of squarecross section.
 5. An assembly according to claim 1 wherein each of saidcores is made of non-metallic material, each panel including a metalsheet overlying each of said top and bottom core surfaces, said sheetsextending between said carpet and the respective surfaces of said cores.6. An assembly according to claim 1 wherein each said core is made frommaterial selected from the group consisting of wood particle board,gypsum board, plywood, light-weight concrete, and light-weight concreteincluding metal reinforcing.